Air-tightness, Carbon Emissions & Health The case for a balanced approach

Transcription

1 Air-tightness, Carbon Emissions & Health The case for a balanced approach Partner Nick Research Cullen hoare & lea Development consulting engineers Hoare Lea & Partners Consulting Engineers

2 Definitions Air Leakage POSITIVE PRESSURE Junctions Uncontrolled movement of air through a buildings Volume of air is dependant upon air tightness Energy & CO 2 WIND SEALS CRACKS FABRIC PENETRATION SEALS SERVICES DISTRIBUTION UK Building Stock 40% of all energy use Air leakage can account for 30% Heat Loss (or more) FLOOR VOID Limited data Naturally Cooled and Ventilated office Improving air tightness is a cost effective means of reducing CO 2 emissions

3 Pictures courtesy of BSRIA

4 Cumulative frequency (%) ALL PARTY PARLIAMENTARY GROUP FOR EXCELLENCE IN THE BUILT ENVIRONMENT Air Leakage of a sample of UK Non-Domestic Buildings (BSRIA Data, Year: 2000) Tight Leaky The overriding conclusion is that an office building can have an air leakage anywhere between 10 and 40 m 3 /h/m 2 BSRIA (1995) Average of Buildings tested Air Leakage@ 50Pa (m 3 /hour per m 2 envelope) Source: Air Leakage Data from BRE/BSRIA Database (CIBSE Journal)

5 Cumulative frequency (%) ALL PARTY PARLIAMENTARY GROUP FOR EXCELLENCE IN THE BUILT ENVIRONMENT Air Leakage of a sample of UK Non-Domestic Buildings (Year: 2000) Tight Leaky 50 Average of Buildings tested PassivHaus No barriers to achieving 2/3 Building Regulations Part L (minimum) Building Regulations Part L (advantageous) Air Leakage@ 50Pa (m 3 /hour per m 2 envelope) Source: Air Leakage Data from BRE/BSRIA Database (CIBSE Journal)

6 Benefits of Air Tight Buildings Energy efficient Reduced CO 2 emissions Energy Due to leakage Actual 10 m 3 /hr/m 2 5 m 3 /hr/m 2 Building No. Source: BSRIA TECHNICAL NOTE TN 8/95

7 Benefits of Air Tight Buildings Energy efficient Reduced CO 2 emissions Improved comfort Proxy Measure of Build Quality

8 Benefits of Air Tight Buildings Energy efficient Reduced CO 2 emissions Improved comfort Proxy Measure of Build Quality But Outdoor air is required to maintain Indoor Air Quality Indoor Air Quality controlled through VENTILATION

9 Ventilation Comfort Odour Healthy environment Moisture Pollutants Bacteria & Viruses Moulds & Fungi Ozone Fibers Tobacco Smoke Eye Irritation Dry Throat Runny Nose Headache Sinus Problems Coughing Fatigue Inorganic Chemicals Organic Chemicals Vehicle fumes Pollens & Dusts Formaldehyde Poor Indoor Air Quality Overlapping Symptomology Replace with Fresh outdoor air +Radon +CO +PM10 +NOx

10 Ventilation Mechanisms Air leakage Un controllable Can cause discomfort Wasteful of energy Openable windows/ Trickle ventilators Natural Ventilation Weather dependant Can cause discomfort Better Control No heat recovery Mechanical ventilation systems Variety (extract only / supply and extract) Control of temperature and quantity Heat recovery Maintenance

11 Energy & CO 2 emissions Comfort, health & Well-being Air-tightness of Buildings

12 Energy & CO 2 emissions Comfort, health & Well-being Air-permeability Air-tightness of Buildings Ventilation

13 Energy & CO 2 emissions Health & Wellbeing Air-permeability Air-tightness of Buildings Ventilation BUILD TIGHT, VENTILATE RIGHT BUILDING REGULATIONS Part L Part F Hierarchical approach to ventilation design

14 Low Carbon Construction Innovation & Growth Team Report Recommendation 8.3: That to avoid the risk of a new generation of sick buildings, the promotion of the health and well-being of occupiers should be placed on an equal footing with the current emphasis on carbon reduction. Recommendation 8.4: That the industry should agree and implement Indoor Air Quality standards to include Indoor Air Quality plans, and enforceable targets for a maximum allowable concentration of toxic contaminants and emissions in interior environments

15 Conclusion Air Tightness is an essential Part of Low Carbon Design Measures to improve air-tightness must be accompanied by measures to ensure ventilation NOW 4 BUILDING OCCUPANT/HEALTH PRODUCTIVITY 3 2 GOOD RESPONSE POOR RESPONSE 3 2 BUILDING ENERGY USE 1 1

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